Behaviour disorder in monosomy 10qter

An Integrated Phenotypic and Genotypic Approach Reveals a High-Risk Subtype Association for EBF3 Missense Variants Affecting the Zinc Finger Domain

OBJECTIVE

Collier/Olf/EBF (COE) transcription factors have distinct expression patterns in the developing and mature nervous system. To date, a neurological disease association has been conclusively established for only the Early B-cell Factor-3 (EBF3) COE family member through the identification of heterozygous loss-of-function variants in individuals with autism spectrum/neurodevelopmental disorders (NDD). Here, we identify a symptom severity risk association with missense variants primarily disrupting the zinc finger domain (ZNF) in EBF3-related NDD.

METHODS

A phenotypic assessment of 41 individuals was combined with a literature meta-analysis for a total of 83 individuals diagnosed with EBF3-related NDD. Quantitative diagnostic phenotypic and symptom severity scales were developed to compare EBF3 variant type and location to identify genotype-phenotype correlations. To stratify the effects of EBF3 variants disrupting either the DNA-binding domain (DBD) or the ZNF, we used in vivo fruit fly UAS-GAL4 expression and in vitro luciferase assays.

RESULTS

We show that patient symptom severity correlates with EBF3 missense variants perturbing the ZNF, which is a key protein domain required for stabilizing the interaction between EBF3 and the target DNA sequence. We found that ZNF-associated variants failed to restore viability in the fruit fly and impaired transcriptional activation. However, the recurrent variant EBF3 p.Arg209Trp in the DBD is capable of partially rescuing viability in the fly and preserved transcriptional activation.

INTERPRETATION

We describe a symptom severity risk association with ZNF perturbations and EBF3 loss-of-function in the largest reported cohort to date of EBF3-related NDD patients. This analysis should have potential predictive clinical value for newly identified patients with EBF3 gene variants. ANN NEUROL 2022;92:138-153.

A Case of Inherited t(4;10)(q26;q26.2) Chromosomal Translocation Elucidated by Multiple Chromosomal and Molecular Analyses. Case Report and Review of the Literature

We present a complex chromosomal anomaly identified using cytogenetic and molecular methods. The child was diagnosed during the neonatal period with a multiple congenital anomalies syndrome characterized by: flattened occipital region; slight turricephaly; tall and broad forehead; hypertelorism; deep-set eyes; down slanting and short palpebral fissures; epicanthic folds; prominent nose with wide root and bulbous tip; microstomia; micro-retrognathia, large, short philtrum with prominent reliefs; low set, prominent ears; and congenital heart disease. The GTG banding karyotype showed a 46,XY,der(10)(10pter→10q26.2::4q26→4qter) chromosomal formula and his mother presented an apparently balanced reciprocal translocation: 46,XX,t(4;10)(q26;q26.2). The chromosomal anomalies of the child were confirmed by MLPA, and supplementary investigation discovered a quadruplication of the 4q35.2 region. The mother has a triplication of the same chromosomal fragment (4q35.2). Using array-CGH, we described the anomalies completely. Thus, the boy has a 71,057 kb triplication of the 4q26-q35.2 region, a 562 kb microdeletion in the 10q26.3 region, and a 795 kb quadruplication of the 4q35.2 region, while the mother presents a 795 kb triplication of the 4q35.2 region. Analyzing these data, we consider that the boy's phenotype is influenced only by the 4q partial trisomy. We compare our case with similar cases, and we review the literature data.

Prenatal diagnosis of concomitant distal 5q duplication and terminal 10q deletion in a fetus with intrauterine growth restriction, congenital diaphragmatic hernia and congenital heart defects

OBJECTIVE

We present prenatal diagnosis of concomitant distal 5q duplication and terminal 10q deletion in a fetus with intrauterine growth restriction (IUGR), congenital diaphragmatic hernia (CDH) and congenital heart defects (CHD).

CASE REPORT

A 34-year-old, gravida 4, para 2, woman was referred for amniocentesis at 21 weeks of gestation because of advanced maternal age and IUGR. There was no congenital malformation in the family. Amniocentesis revealed a derivative chromosome 10 with an additional maternal on the terminal region of 10q. Array comparative genomic hybridization (aCGH) analysis on the DNA extracted from the cultured amniocytes revealed a result of arr 5q31.3q35.5 (142, 548, 354-180,696,806) × 3.0, arr 10q26.3 (132, 932, 808-135,434,178) × 1.0 [GRCh37 (hg19)] with a 2.50-Mb deletion of 10q26.3 encompassing 19 [Online Mendelian Inheritance in Man (OMIM)] genes and a 38.15-Mb duplication of 5q31.3-q35.5 encompassing 195 OMIM genes including four CDH candidate genes of NDST1, ADAM19, NSD1 and MAML1. The mother was found to have a karyotype of 46,XX,t(5; 10) (q31.3; q26.3). Therefore, the fetal karyotype was 46,XX,der(10)t(5; 10)(q31.3; q26.3)mat. Prenatal ultrasound showed IUGR, right CDH, transposition of great artery, double outlet of right ventricle and right atrial isomerism. The pregnancy was terminated, and a malformed fetus was delivered with facial dysmorphism.

CONCLUSION

Fetuses with concomitant distal 5q duplication and terminal 10q deletion may present IUGR, CDH and CHD on prenatal ultrasound.

Whole Gene Deletion of EBF3 Supporting Haploinsufficiency of This Gene as a Mechanism of Neurodevelopmental Disease

Mutations in early B cell factor 3 (EBF3) were recently described in patients with a neurodevelopmental disorder (NDD) that includes developmental delay/intellectual disability, ataxia, hypotonia, speech impairment, strabismus, genitourinary abnormalities, and mild facial dysmorphisms. Several large 10q terminal and interstitial deletions affecting many genes and including EBF3 have been described in the literature. However, small deletions (<1 MB) affecting almost exclusively EBF3 are not commonly reported. We performed array comparative genomic hybridization (aCGH) (Agilent 180K) and quantitative PCR analysis in a female patient with intellectual disability. A clinical comparison between our patient and overlapping cases reported in the literature was also made. The patient carries a de novo 600 Kb deletion at 10q26.3 affecting the MGMT, EBF3, and GLRX genes. The patient has severe intellectual disability, language impairment, conductive hearing loss, hypotonia, vision alterations, triangular face, short stature, and behavior problems. This presentation overlaps that reported for patients carrying EBF3 heterozygous point mutations, as well as literature reports of patients carrying large 10qter deletions. Our results and the literature review suggest that EBF3 haploinsufficiency is a key contributor to the common aspects of the phenotype presented by patients bearing point mutations and indels in this gene, given that deletions affecting the entire gene (alone or in addition to other genes) are causative of a similar syndrome, including intellectual disability (ID) with associated neurological symptoms and particular facial dysmorphisms.

Persistence of müllerian duct structures in a genetic male with distal monosomy 10q

Persistent müllerian duct syndrome (PMD) with antimüllerian hormone (AMH) deficiency is usually associated with mutations or deletions of the AMH gene, although many cases have no identified gene association. We report on a genetic male with PMD and AMH deficiency associated with distal monosomy 10q. A term 3,230 g infant was born to a healthy 27-year-old. Fetal ultrasound had shown possible genital ambiguity. Postnatal exam showed a 0.5 cm phallus with basal meatus, normal scrotum with no palpable gonads, no vaginal orifice, and a rectal fistula with an imperforate anus. Voiding cystourethrogram with ultrasound, cystoscopy, and laparoscopy showed normal bladder, urethral orifice, distal vagina, cervix, and bilateral abdominal testis. At 24 hours of life, testosterone was within normal range with low AMH level. Chromosome microarray analysis showed 46, XY, del10(10q25.3q26.13) involving an 8.2 MB interstitial deletion. Whole exome sequencing identified a NOTCH2 variant (1p11.2). AMH sequencing revealed no abnormalities. Following multidisciplinary team and parent discussion, male gender was assigned. Testosterone treatment resulted in penile length of 1.5 cm. Bilateral orchiopexy and posterior sagittal anorectoplasty were performed at 11 months of age; rudimentary müllerian structures were identified. This observation suggests an association of 10qter elements with male differentiation including AMH expression and is similar to a patient with 46, XY, del(10q26.1) in which AMH levels were not reported. Regional candidate genes include FGFR2 (10q26.13). The possible contribution of a NOTCH2 variant cannot be excluded.

Genetics of bipolar disorder

Bipolar disorder is a common, complex genetic disorder, but the mode of transmission remains to be discovered. Many researchers assume that common genomic variants carry some risk for manifesting the disease. The research community has celebrated the first genome-wide significant associations between common single nucleotide polymorphisms (SNPs) and bipolar disorder. Currently, attempts are under way to translate these findings into clinical practice, genetic counseling, and predictive testing. However, some experts remain cautious. After all, common variants explain only a very small percentage of the genetic risk, and functional consequences of the discovered SNPs are inconclusive. Furthermore, the associated SNPs are not disease specific, and the majority of individuals with a "risk" allele are healthy. On the other hand, population-based genome-wide studies in psychiatric disorders have rediscovered rare structural variants and mutations in genes, which were previously known to cause genetic syndromes and monogenic Mendelian disorders. In many Mendelian syndromes, psychiatric symptoms are prevalent. Although these conditions do not fit the classic description of any specific psychiatric disorder, they often show nonspecific psychiatric symptoms that cross diagnostic boundaries, including intellectual disability, behavioral abnormalities, mood disorders, anxiety disorders, attention deficit, impulse control deficit, and psychosis. Although testing for chromosomal disorders and monogenic Mendelian disorders is well established, testing for common variants is still controversial. The standard concept of genetic testing includes at least three broad criteria that need to be fulfilled before new genetic tests should be introduced: analytical validity, clinical validity, and clinical utility. These criteria are currently not fulfilled for common genomic variants in psychiatric disorders. Further work is clearly needed before genetic testing for common variants in psychiatric disorders should be established.

Complex distal 10q rearrangement in a girl with mild intellectual disability: follow up of the patient and review of the literature of non-acrocentric satellited chromosomes

We report on an intellectually disabled girl with a de novo satellited chromosome 10 (10qs) and performed a review of the literature of the non-acrocentric satellited chromosomes (NASC). Satellites and stalks normally occur on the short arms of acrocentric chromosomes; however, the literature cites several reports of satellited non-acrocentric chromosomes, which presumably result from a translocation with an acrocentric chromosome. This is, to our knowledge, the third report of a 10qs chromosome. The phenotype observed in the proband prompted a search for a structural rearrangement of chromosome 10q. By microsatellite analysis we observed a 4 Mb deletion on the long arm of chromosome 10, approximately 145 kb from the telomere. FISH and array CGH analyses revealed a complex rearrangement involving in range from the centromere to the telomere: A 9.64 Mb 10q26.11-q26.2 duplication, a 1.3 Mb region with no copy number change, followed by a 5.62 Mb 10q26.2-q26.3 deletion and a translocation of satellite material. The homology between the repeat sequences at 10q subtelomere region and the sequences on the acrocentric short arms may explain the origin of the rearrangement and it is likely that the submicroscopic microdeletion and microduplication are responsible for the abnormal phenotype in our patient. The patient presented here, with a 15-year follow-up, manifests a distinct phenotype different from the 10q26 pure distal monosomy and trisomy syndromes.

A subterminal deletion of the long arm of chromosome 10: a clinical report and review

We report on a girl with mental retardation, dysmorphic features, and behavioral problems. A small terminal deletion of the long arm of chromosome 10 was detected by subtelomeric fluorescence in situ hybridization (FISH) studies in all analyzed metaphases. The deletion was shown to be a de novo terminal deletion of approximately 6.1 Mb, with the deletion breakpoint localized at band 10q26.2, between BAC probes RP11-498K22 and RP11-42K2. A subterminal 10q deletion as found in the present patient has, to our knowledge, only been reported in 15 patients (including 8 familial cases). We review the clinical and behavioral phenotype of these patients with "pure" subterminal 10q deletion.

Interstitial deletion del(10)(q25.2q25.3 approximately 26.11)--case report and review of the literature

OBJECTIVES

To present the clinical, cytogenetic, and molecular cytogenetic findings of prenatally diagnosed interstitial deletion 10q25.2-q26.1. The majority of distal 10q deletions are pure terminal deletions with breakpoints in 10q25 and 10q26. Only four patients have been described so far with interstitial deletions involving bands 10q25.2-q26.1.

METHODS

Postmortem physical examination and autopsy of the foetus after medically terminated pregnancy. GTG-banding, reverse painting, and FISH analysis with BAC clones on amniocyte metaphases were performed to determine the extent of the deletion.

RESULTS

At 20 weeks the eutrophic female foetus showed pronounced microretrogeny and hypertelorism, clubfeet as well as minor internal anomalies like pancreas anulare, atypically lobed liver, and missing choleocystis. Cardiac anomalies were not observed and the genitalia were of a normal female. The deletion encompasses 6-Mb and is associated with hemizygosity for 30 genes, including the genes for beta-tectorin, the beta-1 adrenergic receptor, and the alpha-2A adrenergic receptor.

CONCLUSION

An interstitial deletion del(10)(q25.2q25.3 approximately 26.11) was confirmed by FISH with mapped BAC clones. Clinical and molecular cytogenetic analyses of further interstitial 10q deletions are necessary to assess whether the phenotypic manifestations differ between deletions that are interstitial compared to those that include also the terminal region of chromosome 10.

Deletion of the distal long arm of chromosome 10; is there a characteristic phenotype? A report of 15 de novo and familial cases

It has been suggested previously that patients with terminal deletions of chromosome 10q have a recognizable phenotype including a characteristic facial appearance combined with other abnormalities including mental retardation, cardiac and anogenital anomalies. We report the largest published series of new cases of terminal 10q deletion, including eight familial and four de novo cases and three cases with interstitial deletions involving chromosome bands 10q25.2-26.3. The deleted regions were defined by FISH using YAC probes, as well as standard karyotyping. The most consistent clinical features in our cases are cranial anomalies including facial asymmetry, prominent nose and nasal bridge, prominent ears, thin upper lip, along with growth retardation, developmental delay, and digital abnormalities. Visceral abnormalities were only identified in a small number of the patients, with renal involvement in three cases and structural cardiac malformations in two others. Learning difficulties of varying severity were found in 11 cases and behavioral problems described in four. Candidate genes for behavioral and learning difficulties within the deleted region include Calcyon. Other genes in the region that might have a role in causing the phenotype include the genes coding for fibroblast growth factor receptor type 2 (FGFR2) and C-terminal binding protein 2 (CTBP2).

Terminal deletion of the long arm of chromosome 10

The case of two female patients with de novo terminal deletion of the long arm of chromosome 10, one with del(10)(q26.2) and the other with del(10)(q26.3), is reported. Both presented with megabladder associated with urinary tract abnormalities. The case of four similar patients has been previously reported with bladder dilatation secondary to urinary obstruction. These new cases highlight the possible involvement of the bladder and the urethra in the syndrome of chromosome 10q terminal deletion, suggesting a careful renal and urinary tract evaluation in such situations. Moreover, the possibility of monosomy 10qter syndrome should be borne in mind in the case of prenatal diagnosis of apparently isolated bladder obstruction, especially in females.

Developmental profile in a patient with monosomy 10q and dup(17p) associated with a peripheral neuropathy

We report on a patient with dup(17p) and monosomy (10q) resulting from a familial translocation. Manifestations typical of both syndromes were present. The overall development of this patient was better by comparison with similar reported cases of either anomaly. Our evaluation detected severe gross motor delay and signs of a demyelinating peripheral neuropathy. This patient is trisomic for the region of 17p which includes the peripheral myelin protein-22 (PMP-22) gene, known to be duplicated in Charcot-Marie-Tooth neuropathy type 1A (CMT1A). Our analysis in this patient suggests that trisomy for the PMP-22 gene led to the demyelinating neuropathy and contributed to his severe motor developmental delay.

An epidemiological study of isolated split hand/foot in Hungary, 1975-1984

A population based and validated 10 year cohort of 94 cases with split hand/foot born in Hungary, 1975-1984 was evaluated. This type of congenital limb deficiency was relatively frequently (43%) associated with non-limb defects. Fifty-four cases with isolated split hand/foot are evaluated in this paper. A single limb was affected in 78% of cases. The upper limbs were 21 times more frequently affected in unimelic cases with a right sided predominance and male excess. Case-control analysis indicated intrauterine growth retardation and lower socioeconomic status of parents of cases. Family study showed six familial cases with autosomal dominant inheritance among 152 first and 452 second degree relatives. All familial cases were males.

Complete and partial XY sex reversal associated with terminal deletion of 10q: report of 2 cases and literature review

We describe 2 karyotypically male infants with terminal deletion of 10q and mental retardation, multiple phenotypic anomalies and abnormal genitalia. One [karyotype 46,XY, del(10)(q26.1)] had female external genitalia; the other [karyotype 46,XY,-10,+der(10)t (10;16)(q26.2;q21)] had an intersex phenotype. Of 8 males previously reported with terminal 10q deletion as the major or only cytogenetic abnormality, 2 had an intersex phenotype, and the others all had combinations of cryptorchidism, micropenis, and hypospadias. Terminal 10q deletions appear to be strongly associated with abnormal male genital development, and should be specifically searched for in the cytogenetic workup of such cases.

The psychiatric, psychological and behavioural functioning of a boy with terminal deletion of the long arm of chromosome 10

The developmental and behavioural functioning of a six-year-old boy with deletion of the long arm of chromosome 10 was evaluated using reliable, standardised, psychological inventories. The information obtained clarified his complex pattern of strengths and needs; it also contributes scientifically derived data to the literature on behavioural correlates of this condition.

Monosomy 10qter: a new case

A new case of terminal deletion 10q26-qter is described. The phenotypic features are compatible with those of the previously reported cases. Deafness is reported for the first time.

A familial MCA/MR syndrome due to translocation t(10;16) (q26;p13.1): report of six cases

A minute familial translocation t(10;16) (q26;p13.1) was detected in a family with 6 affected children in 2 generations and 9 carriers in 3 generations. This apparently unique translocation is associated with a deleterious syndrome which includes fetal hydrops, ascites, complex congenital heart defect, psychomotor retardation, failure to thrive, hypotonia, narrow palpebral fissures, abnormally modeled, apparently low-set ears, cleft palate, thumb abnormalities, hypogenitalism, inguinal hernia, and sparse hair. All children of known or presumed carriers have been either balanced or unbalanced carriers of this translocation.

A case of two inversion (10) recombinants in a family

A family is described in which the mother's four pregnancies resulted in one spontaneous abortion, one healthy boy, and a male and female sib with developmental delay and multiple minor dysmorphic features. Chromosome analysis showed a large pericentric inversion of chromosome 10, involving the region between bands p15.1 and q25.2, in the father and the healthy son: 46,XY,inv(10) (p15.1q25.2), and an unbalanced karyotype in the two affected sibs: rec(10),dup p,inv(10) (p15.1q25.2). The unbalanced chromosome has been produced by meiotic recombination between the inversion chromosome and its normal homologue. The two affected sibs have partial duplication of 10p and partial deficiency of 10q, and share a large number of clinical features, several of which have previously been described in both of these chromosome imbalances. We believe this to be the largest pericentric inversion of chromosome 10 reported to have produced recombinant offspring.

Chromosome 10qter deletion syndrome: a review and report of three new cases

We report on three patients with terminal deletions of chromosome 10q and compare them to 15 previously reported patients. A similar facial appearance with a prominent beaked nose, large and/or malformed ears, and a pattern of major abnormalities including severe mental retardation, cardiac anomalies, and anogenital anomalies are reviewed. We feel the manifestations of del 10qter are sufficiently distinct to suggest this diagnosis on clinical examination.

A case of interstitial deletion of 10q25.2----q26.1

A de novo interstitial deletion of chromosome 10, del(10)(pter----q25.2::q26.1----qter), was detected in a newborn female with facial anomalies, failure to thrive, and subsequent developmental delay. This case is compared with 10 previous reports of monosomy 10q within the q25----qter region.